[fio.git] / log.c

/*
 * Code related to writing an iolog of what a thread is doing, and to
 * later read that back and replay
 */
#include <stdio.h>
#include <stdlib.h>
#include <libgen.h>
#include <assert.h>
#include "flist.h"
#include "fio.h"
#include "verify.h"

static const char iolog_ver2[] = "fio version 2 iolog";

void queue_io_piece(struct thread_data *td, struct io_piece *ipo)
{
	flist_add_tail(&ipo->list, &td->io_log_list);
	td->total_io_size += ipo->len;
}

void log_io_u(struct thread_data *td, struct io_u *io_u)
{
	const char *act[] = { "read", "write", "sync", "datasync",
				"sync_file_range" };

	assert(io_u->ddir <= 4);

	if (!td->o.write_iolog_file)
		return;

	fprintf(td->iolog_f, "%s %s %llu %lu\n", io_u->file->file_name,
						act[io_u->ddir], io_u->offset,
						io_u->buflen);
}

void log_file(struct thread_data *td, struct fio_file *f,
	      enum file_log_act what)
{
	const char *act[] = { "add", "open", "close" };

	assert(what < 3);

	if (!td->o.write_iolog_file)
		return;


	/*
	 * this happens on the pre-open/close done before the job starts
	 */
	if (!td->iolog_f)
		return;

	fprintf(td->iolog_f, "%s %s\n", f->file_name, act[what]);
}

static void iolog_delay(struct thread_data *td, unsigned long delay)
{
	unsigned long usec = utime_since_now(&td->last_issue);

	if (delay < usec)
		return;

	delay -= usec;

	/*
	 * less than 100 usec delay, just regard it as noise
	 */
	if (delay < 100)
		return;

	usec_sleep(td, delay);
}

static int ipo_special(struct thread_data *td, struct io_piece *ipo)
{
	struct fio_file *f;
	int ret;

	/*
	 * Not a special ipo
	 */
	if (ipo->ddir != DDIR_INVAL)
		return 0;

	f = td->files[ipo->fileno];

	switch (ipo->file_action) {
	case FIO_LOG_OPEN_FILE:
		ret = td_io_open_file(td, f);
		if (!ret)
			break;
		td_verror(td, ret, "iolog open file");
		return -1;
	case FIO_LOG_CLOSE_FILE:
		td_io_close_file(td, f);
		break;
	case FIO_LOG_UNLINK_FILE:
		unlink(f->file_name);
		break;
	default:
		log_err("fio: bad file action %d\n", ipo->file_action);
		break;
	}

	return 1;
}

int read_iolog_get(struct thread_data *td, struct io_u *io_u)
{
	struct io_piece *ipo;
	unsigned long elapsed;
	
	while (!flist_empty(&td->io_log_list)) {
		int ret;

		ipo = flist_entry(td->io_log_list.next, struct io_piece, list);
		flist_del(&ipo->list);

		ret = ipo_special(td, ipo);
		if (ret < 0) {
			free(ipo);
			break;
		} else if (ret > 0) {
			free(ipo);
			continue;
		}

		io_u->ddir = ipo->ddir;
		if (ipo->ddir != DDIR_WAIT) {
			io_u->offset = ipo->offset;
			io_u->buflen = ipo->len;
			io_u->file = td->files[ipo->fileno];
			get_file(io_u->file);

			dprint(FD_IO, "iolog: get %llu/%lu/%s\n", io_u->offset,
						io_u->buflen, io_u->file->file_name);
			if (ipo->delay) iolog_delay(td, ipo->delay);
		} else {
			elapsed = mtime_since_genesis();
			if (ipo->delay > elapsed)
				usec_sleep(td, (ipo->delay - elapsed) * 1000);
				
		}

		free(ipo);
		
		if (ipo->ddir != DDIR_WAIT)
			return 0;
	}

	td->done = 1;
	return 1;
}

void prune_io_piece_log(struct thread_data *td)
{
	struct io_piece *ipo;
	struct rb_node *n;

	while ((n = rb_first(&td->io_hist_tree)) != NULL) {
		ipo = rb_entry(n, struct io_piece, rb_node);
		rb_erase(n, &td->io_hist_tree);
		free(ipo);
	}

	while (!flist_empty(&td->io_hist_list)) {
		ipo = flist_entry(td->io_hist_list.next, struct io_piece, list);
		flist_del(&ipo->list);
		free(ipo);
	}
}

/*
 * log a successful write, so we can unwind the log for verify
 */
void log_io_piece(struct thread_data *td, struct io_u *io_u)
{
	struct rb_node **p, *parent;
	struct io_piece *ipo, *__ipo;

	ipo = malloc(sizeof(struct io_piece));
	ipo->file = io_u->file;
	ipo->offset = io_u->offset;
	ipo->len = io_u->buflen;

	/*
	 * We don't need to sort the entries, if:
	 *
	 *	Sequential writes, or
	 *	Random writes that lay out the file as it goes along
	 *
	 * For both these cases, just reading back data in the order we
	 * wrote it out is the fastest.
	 *
	 * One exception is if we don't have a random map AND we are doing
	 * verifies, in that case we need to check for duplicate blocks and
	 * drop the old one, which we rely on the rb insert/lookup for
	 * handling.
	 */
	if ((!td_random(td) || !td->o.overwrite) &&
	      (file_randommap(td, ipo->file) || td->o.verify == VERIFY_NONE)) {
		INIT_FLIST_HEAD(&ipo->list);
		flist_add_tail(&ipo->list, &td->io_hist_list);
		return;
	}

	RB_CLEAR_NODE(&ipo->rb_node);

	/*
	 * Sort the entry into the verification list
	 */
restart:
	p = &td->io_hist_tree.rb_node;
	parent = NULL;
	while (*p) {
		parent = *p;

		__ipo = rb_entry(parent, struct io_piece, rb_node);
		if (ipo->offset < __ipo->offset)
			p = &(*p)->rb_left;
		else if (ipo->offset > __ipo->offset)
			p = &(*p)->rb_right;
		else {
			assert(ipo->len == __ipo->len);
			rb_erase(parent, &td->io_hist_tree);
			goto restart;
		}
	}

	rb_link_node(&ipo->rb_node, parent, p);
	rb_insert_color(&ipo->rb_node, &td->io_hist_tree);
}

void write_iolog_close(struct thread_data *td)
{
	fflush(td->iolog_f);
	fclose(td->iolog_f);
	free(td->iolog_buf);
	td->iolog_f = NULL;
	td->iolog_buf = NULL;
}

/*
 * Read version 2 iolog data. It is enhanced to include per-file logging,
 * syncs, etc.
 */
static int read_iolog2(struct thread_data *td, FILE *f)
{
	unsigned long long offset;
	unsigned int bytes;
	int reads, writes, waits, fileno = 0, file_action = 0; /* stupid gcc */
	char *fname, *act;
	char *str, *p;
	enum fio_ddir rw;

	free_release_files(td);

	/*
	 * Read in the read iolog and store it, reuse the infrastructure
	 * for doing verifications.
	 */
	str = malloc(4096);
	fname = malloc(256+16);
	act = malloc(256+16);

	reads = writes = waits = 0;
	while ((p = fgets(str, 4096, f)) != NULL) {
		struct io_piece *ipo;
		int r;

		r = sscanf(p, "%256s %256s %llu %u", fname, act, &offset,
									&bytes);
		if (r == 4) {
			/*
			 * Check action first
			 */
			if (!strcmp(act, "wait"))
				rw = DDIR_WAIT;
			else if (!strcmp(act, "read"))
				rw = DDIR_READ;
			else if (!strcmp(act, "write"))
				rw = DDIR_WRITE;
			else if (!strcmp(act, "sync"))
				rw = DDIR_SYNC;
			else if (!strcmp(act, "datasync"))
				rw = DDIR_DATASYNC;
			else {
				log_err("fio: bad iolog file action: %s\n",
									act);
				continue;
			}
		} else if (r == 2) {
			rw = DDIR_INVAL;
			if (!strcmp(act, "add")) {
				td->o.nr_files++;
				fileno = add_file(td, fname);
				file_action = FIO_LOG_ADD_FILE;
				continue;
			} else if (!strcmp(act, "open")) {
				fileno = get_fileno(td, fname);
				file_action = FIO_LOG_OPEN_FILE;
			} else if (!strcmp(act, "close")) {
				fileno = get_fileno(td, fname);
				file_action = FIO_LOG_CLOSE_FILE;
			} else {
				log_err("fio: bad iolog file action: %s\n",
									act);
				continue;
			}
		} else {
			log_err("bad iolog2: %s", p);
			continue;
		}

		if (rw == DDIR_READ)
			reads++;
		else if (rw == DDIR_WRITE) {
			/*
			 * Don't add a write for ro mode
			 */
			if (read_only)
				continue;
			writes++;
		} else if (rw == DDIR_WAIT) {
			waits++;
		} else if (rw == DDIR_INVAL) {
		} else if (!ddir_sync(rw)) {
			log_err("bad ddir: %d\n", rw);
			continue;
		}

		/*
		 * Make note of file
		 */
		ipo = malloc(sizeof(*ipo));
		memset(ipo, 0, sizeof(*ipo));
		INIT_FLIST_HEAD(&ipo->list);
		ipo->ddir = rw;
		if (rw == DDIR_WAIT) {
			ipo->delay = offset;
		} else {
			ipo->offset = offset;
			ipo->len = bytes;
			if (bytes > td->o.max_bs[rw])
				td->o.max_bs[rw] = bytes;
			ipo->fileno = fileno;
			ipo->file_action = file_action;
		}
			
		queue_io_piece(td, ipo);
	}

	free(str);
	free(act);
	free(fname);

	if (writes && read_only) {
		log_err("fio: <%s> skips replay of %d writes due to"
			" read-only\n", td->o.name, writes);
		writes = 0;
	}

	if (!reads && !writes && !waits)
		return 1;
	else if (reads && !writes)
		td->o.td_ddir = TD_DDIR_READ;
	else if (!reads && writes)
		td->o.td_ddir = TD_DDIR_WRITE;
	else
		td->o.td_ddir = TD_DDIR_RW;

	return 0;
}

/*
 * open iolog, check version, and call appropriate parser
 */
static int init_iolog_read(struct thread_data *td)
{
	char buffer[256], *p;
	FILE *f;
	int ret;

	f = fopen(td->o.read_iolog_file, "r");
	if (!f) {
		perror("fopen read iolog");
		return 1;
	}

	p = fgets(buffer, sizeof(buffer), f);
	if (!p) {
		td_verror(td, errno, "iolog read");
		log_err("fio: unable to read iolog\n");
		return 1;
	}

	/*
	 * version 2 of the iolog stores a specific string as the
	 * first line, check for that
	 */
	if (!strncmp(iolog_ver2, buffer, strlen(iolog_ver2)))
		ret = read_iolog2(td, f);
	else {
		log_err("fio: iolog version 1 is no longer supported\n");
		ret = 1;
	}

	fclose(f);
	return ret;
}

/*
 * Setup a log for storing io patterns.
 */
static int init_iolog_write(struct thread_data *td)
{
	struct fio_file *ff;
	FILE *f;
	unsigned int i;

	f = fopen(td->o.write_iolog_file, "a");
	if (!f) {
		perror("fopen write iolog");
		return 1;
	}

	/*
	 * That's it for writing, setup a log buffer and we're done.
	  */
	td->iolog_f = f;
	td->iolog_buf = malloc(8192);
	setvbuf(f, td->iolog_buf, _IOFBF, 8192);

	/*
	 * write our version line
	 */
	if (fprintf(f, "%s\n", iolog_ver2) < 0) {
		perror("iolog init\n");
		return 1;
	}

	/*
	 * add all known files
	 */
	for_each_file(td, ff, i)
		log_file(td, ff, FIO_LOG_ADD_FILE);

	return 0;
}

int init_iolog(struct thread_data *td)
{
	int ret = 0;

	if (td->o.read_iolog_file) {
		/*
		 * Check if it's a blktrace file and load that if possible.
		 * Otherwise assume it's a normal log file and load that.
		 */
		if (is_blktrace(td->o.read_iolog_file))
			ret = load_blktrace(td, td->o.read_iolog_file);
		else
			ret = init_iolog_read(td);
	} else if (td->o.write_iolog_file)
		ret = init_iolog_write(td);

	return ret;
}

void setup_log(struct io_log **log)
{
	struct io_log *l = malloc(sizeof(*l));

	l->nr_samples = 0;
	l->max_samples = 1024;
	l->log = malloc(l->max_samples * sizeof(struct io_sample));
	*log = l;
}

void __finish_log(struct io_log *log, const char *name)
{
	unsigned int i;
	FILE *f;

	f = fopen(name, "a");
	if (!f) {
		perror("fopen log");
		return;
	}

	for (i = 0; i < log->nr_samples; i++) {
		fprintf(f, "%lu, %lu, %u, %u\n", log->log[i].time,
						log->log[i].val,
						log->log[i].ddir,
						log->log[i].bs);
	}

	fclose(f);
	free(log->log);
	free(log);
}

void finish_log_named(struct thread_data *td, struct io_log *log,
		       const char *prefix, const char *postfix)
{
	char file_name[256], *p;

	snprintf(file_name, 200, "%s_%s.log", prefix, postfix);
	p = basename(file_name);
	__finish_log(log, p);
}

void finish_log(struct thread_data *td, struct io_log *log, const char *name)
{
	finish_log_named(td, log, td->o.name, name);
}
Commit	Line	Data
	1	/*
	2	* Code related to writing an iolog of what a thread is doing, and to
	3	* later read that back and replay
	4	*/
	5	#include <stdio.h>
	6	#include <stdlib.h>
	7	#include <libgen.h>
	8	#include <assert.h>
	9	#include "flist.h"
	10	#include "fio.h"
	11	#include "verify.h"
	12
	13	static const char iolog_ver2[] = "fio version 2 iolog";
	14
	15	void queue_io_piece(struct thread_data td, struct io_piece ipo)
	16	{
	17	flist_add_tail(&ipo->list, &td->io_log_list);
	18	td->total_io_size += ipo->len;
	19	}
	20
	21	void log_io_u(struct thread_data td, struct io_u io_u)
	22	{
	23	const char *act[] = { "read", "write", "sync", "datasync",
	24	"sync_file_range" };
	25
	26	assert(io_u->ddir <= 4);
	27
	28	if (!td->o.write_iolog_file)
	29	return;
	30
	31	fprintf(td->iolog_f, "%s %s %llu %lu\n", io_u->file->file_name,
	32	act[io_u->ddir], io_u->offset,
	33	io_u->buflen);
	34	}
	35
	36	void log_file(struct thread_data td, struct fio_file f,
	37	enum file_log_act what)
	38	{
	39	const char *act[] = { "add", "open", "close" };
	40
	41	assert(what < 3);
	42
	43	if (!td->o.write_iolog_file)
	44	return;
	45
	46
	47	/*
	48	* this happens on the pre-open/close done before the job starts
	49	*/
	50	if (!td->iolog_f)
	51	return;
	52
	53	fprintf(td->iolog_f, "%s %s\n", f->file_name, act[what]);
	54	}
	55
	56	static void iolog_delay(struct thread_data *td, unsigned long delay)
	57	{
	58	unsigned long usec = utime_since_now(&td->last_issue);
	59
	60	if (delay < usec)
	61	return;
	62
	63	delay -= usec;
	64
	65	/*
	66	* less than 100 usec delay, just regard it as noise
	67	*/
	68	if (delay < 100)
	69	return;
	70
	71	usec_sleep(td, delay);
	72	}
	73
	74	static int ipo_special(struct thread_data td, struct io_piece ipo)
	75	{
	76	struct fio_file *f;
	77	int ret;
	78
	79	/*
	80	* Not a special ipo
	81	*/
	82	if (ipo->ddir != DDIR_INVAL)
	83	return 0;
	84
	85	f = td->files[ipo->fileno];
	86
	87	switch (ipo->file_action) {
	88	case FIO_LOG_OPEN_FILE:
	89	ret = td_io_open_file(td, f);
	90	if (!ret)
	91	break;
	92	td_verror(td, ret, "iolog open file");
	93	return -1;
	94	case FIO_LOG_CLOSE_FILE:
	95	td_io_close_file(td, f);
	96	break;
	97	case FIO_LOG_UNLINK_FILE:
	98	unlink(f->file_name);
	99	break;
	100	default:
	101	log_err("fio: bad file action %d\n", ipo->file_action);
	102	break;
	103	}
	104
	105	return 1;
	106	}
	107
	108	int read_iolog_get(struct thread_data td, struct io_u io_u)
	109	{
	110	struct io_piece *ipo;
	111	unsigned long elapsed;
	112
	113	while (!flist_empty(&td->io_log_list)) {
	114	int ret;
	115
	116	ipo = flist_entry(td->io_log_list.next, struct io_piece, list);
	117	flist_del(&ipo->list);
	118
	119	ret = ipo_special(td, ipo);
	120	if (ret < 0) {
	121	free(ipo);
	122	break;
	123	} else if (ret > 0) {
	124	free(ipo);
	125	continue;
	126	}
	127
	128	io_u->ddir = ipo->ddir;
	129	if (ipo->ddir != DDIR_WAIT) {
	130	io_u->offset = ipo->offset;
	131	io_u->buflen = ipo->len;
	132	io_u->file = td->files[ipo->fileno];
	133	get_file(io_u->file);
	134
	135	dprint(FD_IO, "iolog: get %llu/%lu/%s\n", io_u->offset,
	136	io_u->buflen, io_u->file->file_name);
	137	if (ipo->delay) iolog_delay(td, ipo->delay);
	138	} else {
	139	elapsed = mtime_since_genesis();
	140	if (ipo->delay > elapsed)
	141	usec_sleep(td, (ipo->delay - elapsed) * 1000);
	142
	143	}
	144
	145	free(ipo);
	146
	147	if (ipo->ddir != DDIR_WAIT)
	148	return 0;
	149	}
	150
	151	td->done = 1;
	152	return 1;
	153	}
	154
	155	void prune_io_piece_log(struct thread_data *td)
	156	{
	157	struct io_piece *ipo;
	158	struct rb_node *n;
	159
	160	while ((n = rb_first(&td->io_hist_tree)) != NULL) {
	161	ipo = rb_entry(n, struct io_piece, rb_node);
	162	rb_erase(n, &td->io_hist_tree);
	163	free(ipo);
	164	}
	165
	166	while (!flist_empty(&td->io_hist_list)) {
	167	ipo = flist_entry(td->io_hist_list.next, struct io_piece, list);
	168	flist_del(&ipo->list);
	169	free(ipo);
	170	}
	171	}
	172
	173	/*
	174	* log a successful write, so we can unwind the log for verify
	175	*/
	176	void log_io_piece(struct thread_data td, struct io_u io_u)
	177	{
	178	struct rb_node *p, parent;
	179	struct io_piece ipo, __ipo;
	180
	181	ipo = malloc(sizeof(struct io_piece));
	182	ipo->file = io_u->file;
	183	ipo->offset = io_u->offset;
	184	ipo->len = io_u->buflen;
	185
	186	/*
	187	* We don't need to sort the entries, if:
	188	*
	189	* Sequential writes, or
	190	* Random writes that lay out the file as it goes along
	191	*
	192	* For both these cases, just reading back data in the order we
	193	* wrote it out is the fastest.
	194	*
	195	* One exception is if we don't have a random map AND we are doing
	196	* verifies, in that case we need to check for duplicate blocks and
	197	* drop the old one, which we rely on the rb insert/lookup for
	198	* handling.
	199	*/
	200	if ((!td_random(td) \|\| !td->o.overwrite) &&
	201	(file_randommap(td, ipo->file) \|\| td->o.verify == VERIFY_NONE)) {
	202	INIT_FLIST_HEAD(&ipo->list);
	203	flist_add_tail(&ipo->list, &td->io_hist_list);
	204	return;
	205	}
	206
	207	RB_CLEAR_NODE(&ipo->rb_node);
	208
	209	/*
	210	* Sort the entry into the verification list
	211	*/
	212	restart:
	213	p = &td->io_hist_tree.rb_node;
	214	parent = NULL;
	215	while (*p) {
	216	parent = *p;
	217
	218	__ipo = rb_entry(parent, struct io_piece, rb_node);
	219	if (ipo->offset < __ipo->offset)
	220	p = &(*p)->rb_left;
	221	else if (ipo->offset > __ipo->offset)
	222	p = &(*p)->rb_right;
	223	else {
	224	assert(ipo->len == __ipo->len);
	225	rb_erase(parent, &td->io_hist_tree);
	226	goto restart;
	227	}
	228	}
	229
	230	rb_link_node(&ipo->rb_node, parent, p);
	231	rb_insert_color(&ipo->rb_node, &td->io_hist_tree);
	232	}
	233
	234	void write_iolog_close(struct thread_data *td)
	235	{
	236	fflush(td->iolog_f);
	237	fclose(td->iolog_f);
	238	free(td->iolog_buf);
	239	td->iolog_f = NULL;
	240	td->iolog_buf = NULL;
	241	}
	242
	243	/*
	244	* Read version 2 iolog data. It is enhanced to include per-file logging,
	245	* syncs, etc.
	246	*/
	247	static int read_iolog2(struct thread_data td, FILE f)
	248	{
	249	unsigned long long offset;
	250	unsigned int bytes;
	251	int reads, writes, waits, fileno = 0, file_action = 0; /* stupid gcc */
	252	char fname, act;
	253	char str, p;
	254	enum fio_ddir rw;
	255
	256	free_release_files(td);
	257
	258	/*
	259	* Read in the read iolog and store it, reuse the infrastructure
	260	* for doing verifications.
	261	*/
	262	str = malloc(4096);
	263	fname = malloc(256+16);
	264	act = malloc(256+16);
	265
	266	reads = writes = waits = 0;
	267	while ((p = fgets(str, 4096, f)) != NULL) {
	268	struct io_piece *ipo;
	269	int r;
	270
	271	r = sscanf(p, "%256s %256s %llu %u", fname, act, &offset,
	272	&bytes);
	273	if (r == 4) {
	274	/*
	275	* Check action first
	276	*/
	277	if (!strcmp(act, "wait"))
	278	rw = DDIR_WAIT;
	279	else if (!strcmp(act, "read"))
	280	rw = DDIR_READ;
	281	else if (!strcmp(act, "write"))
	282	rw = DDIR_WRITE;
	283	else if (!strcmp(act, "sync"))
	284	rw = DDIR_SYNC;
	285	else if (!strcmp(act, "datasync"))
	286	rw = DDIR_DATASYNC;
	287	else {
	288	log_err("fio: bad iolog file action: %s\n",
	289	act);
	290	continue;
	291	}
	292	} else if (r == 2) {
	293	rw = DDIR_INVAL;
	294	if (!strcmp(act, "add")) {
	295	td->o.nr_files++;
	296	fileno = add_file(td, fname);
	297	file_action = FIO_LOG_ADD_FILE;
	298	continue;
	299	} else if (!strcmp(act, "open")) {
	300	fileno = get_fileno(td, fname);
	301	file_action = FIO_LOG_OPEN_FILE;
	302	} else if (!strcmp(act, "close")) {
	303	fileno = get_fileno(td, fname);
	304	file_action = FIO_LOG_CLOSE_FILE;
	305	} else {
	306	log_err("fio: bad iolog file action: %s\n",
	307	act);
	308	continue;
	309	}
	310	} else {
	311	log_err("bad iolog2: %s", p);
	312	continue;
	313	}
	314
	315	if (rw == DDIR_READ)
	316	reads++;
	317	else if (rw == DDIR_WRITE) {
	318	/*
	319	* Don't add a write for ro mode
	320	*/
	321	if (read_only)
	322	continue;
	323	writes++;
	324	} else if (rw == DDIR_WAIT) {
	325	waits++;
	326	} else if (rw == DDIR_INVAL) {
	327	} else if (!ddir_sync(rw)) {
	328	log_err("bad ddir: %d\n", rw);
	329	continue;
	330	}
	331
	332	/*
	333	* Make note of file
	334	*/
	335	ipo = malloc(sizeof(*ipo));
	336	memset(ipo, 0, sizeof(*ipo));
	337	INIT_FLIST_HEAD(&ipo->list);
	338	ipo->ddir = rw;
	339	if (rw == DDIR_WAIT) {
	340	ipo->delay = offset;
	341	} else {
	342	ipo->offset = offset;
	343	ipo->len = bytes;
	344	if (bytes > td->o.max_bs[rw])
	345	td->o.max_bs[rw] = bytes;
	346	ipo->fileno = fileno;
	347	ipo->file_action = file_action;
	348	}
	349
	350	queue_io_piece(td, ipo);
	351	}
	352
	353	free(str);
	354	free(act);
	355	free(fname);
	356
	357	if (writes && read_only) {
	358	log_err("fio: <%s> skips replay of %d writes due to"
	359	" read-only\n", td->o.name, writes);
	360	writes = 0;
	361	}
	362
	363	if (!reads && !writes && !waits)
	364	return 1;
	365	else if (reads && !writes)
	366	td->o.td_ddir = TD_DDIR_READ;
	367	else if (!reads && writes)
	368	td->o.td_ddir = TD_DDIR_WRITE;
	369	else
	370	td->o.td_ddir = TD_DDIR_RW;
	371
	372	return 0;
	373	}
	374
	375	/*
	376	* open iolog, check version, and call appropriate parser
	377	*/
	378	static int init_iolog_read(struct thread_data *td)
	379	{
	380	char buffer[256], *p;
	381	FILE *f;
	382	int ret;
	383
	384	f = fopen(td->o.read_iolog_file, "r");
	385	if (!f) {
	386	perror("fopen read iolog");
	387	return 1;
	388	}
	389
	390	p = fgets(buffer, sizeof(buffer), f);
	391	if (!p) {
	392	td_verror(td, errno, "iolog read");
	393	log_err("fio: unable to read iolog\n");
	394	return 1;
	395	}
	396
	397	/*
	398	* version 2 of the iolog stores a specific string as the
	399	* first line, check for that
	400	*/
	401	if (!strncmp(iolog_ver2, buffer, strlen(iolog_ver2)))
	402	ret = read_iolog2(td, f);
	403	else {
	404	log_err("fio: iolog version 1 is no longer supported\n");
	405	ret = 1;
	406	}
	407
	408	fclose(f);
	409	return ret;
	410	}
	411
	412	/*
	413	* Setup a log for storing io patterns.
	414	*/
	415	static int init_iolog_write(struct thread_data *td)
	416	{
	417	struct fio_file *ff;
	418	FILE *f;
	419	unsigned int i;
	420
	421	f = fopen(td->o.write_iolog_file, "a");
	422	if (!f) {
	423	perror("fopen write iolog");
	424	return 1;
	425	}
	426
	427	/*
	428	* That's it for writing, setup a log buffer and we're done.
	429	*/
	430	td->iolog_f = f;
	431	td->iolog_buf = malloc(8192);
	432	setvbuf(f, td->iolog_buf, _IOFBF, 8192);
	433
	434	/*
	435	* write our version line
	436	*/
	437	if (fprintf(f, "%s\n", iolog_ver2) < 0) {
	438	perror("iolog init\n");
	439	return 1;
	440	}
	441
	442	/*
	443	* add all known files
	444	*/
	445	for_each_file(td, ff, i)
	446	log_file(td, ff, FIO_LOG_ADD_FILE);
	447
	448	return 0;
	449	}
	450
	451	int init_iolog(struct thread_data *td)
	452	{
	453	int ret = 0;
	454
	455	if (td->o.read_iolog_file) {
	456	/*
	457	* Check if it's a blktrace file and load that if possible.
	458	* Otherwise assume it's a normal log file and load that.
	459	*/
	460	if (is_blktrace(td->o.read_iolog_file))
	461	ret = load_blktrace(td, td->o.read_iolog_file);
	462	else
	463	ret = init_iolog_read(td);
	464	} else if (td->o.write_iolog_file)
	465	ret = init_iolog_write(td);
	466
	467	return ret;
	468	}
	469
	470	void setup_log(struct io_log **log)
	471	{
	472	struct io_log l = malloc(sizeof(l));
	473
	474	l->nr_samples = 0;
	475	l->max_samples = 1024;
	476	l->log = malloc(l->max_samples * sizeof(struct io_sample));
	477	*log = l;
	478	}
	479
	480	void __finish_log(struct io_log log, const char name)
	481	{
	482	unsigned int i;
	483	FILE *f;
	484
	485	f = fopen(name, "a");
	486	if (!f) {
	487	perror("fopen log");
	488	return;
	489	}
	490
	491	for (i = 0; i < log->nr_samples; i++) {
	492	fprintf(f, "%lu, %lu, %u, %u\n", log->log[i].time,
	493	log->log[i].val,
	494	log->log[i].ddir,
	495	log->log[i].bs);
	496	}
	497
	498	fclose(f);
	499	free(log->log);
	500	free(log);
	501	}
	502
	503	void finish_log_named(struct thread_data td, struct io_log log,
	504	const char prefix, const char postfix)
	505	{
	506	char file_name[256], *p;
	507
	508	snprintf(file_name, 200, "%s_%s.log", prefix, postfix);
	509	p = basename(file_name);
	510	__finish_log(log, p);
	511	}
	512
	513	void finish_log(struct thread_data td, struct io_log log, const char *name)
	514	{
	515	finish_log_named(td, log, td->o.name, name);
	516	}